[KUDU-1075] metrics entities need to retire

• Type: Bug
• Status: Resolved
• Priority: Critical
• Resolution: Fixed
• Affects Version/s: Private Beta
• Component/s: metrics
• Target Version/s: Public beta
• Code Review: http://gerrit.sjc.cloudera.com:8080/7674
• Assignee: Todd Lipcon
• Reporter: Todd Lipcon
• Created: 27/Aug/15 13:35
• Updated: 31/Aug/15 02:10
• Resolved: 31/Aug/15 02:10

Description

Chris noticed that our metrics endpoints keep on reporting tablets even after their tables have been deleted. I found that I had left a TODO to actually retire expired metric entities but didn't implement it. We need this to avoid CM having to fetch ever larger-and-larger metrics pages in the case that someone is creating/dropping tables regularly.